Casing spider and the like



Jan. 21, 1930. R. H. FOLSOM 4,

CASING SPIDER AND THE LIKE Filed March 25, 1928 2 Sheets-Sheet 1 I N VENTOR.

Jan. 21, 1930.- R. H. FOLSOM' 44, 8

CASING SPIDER AND THE LIKE Filed March 25, 1928 2 Sheets-Sheet 2INVENTOR.

Patented Jan. 21, 1930 ROBERT E. FOLSOM, OF LOS ANGELES, CALIFORNIA,ASSIGNOR TO JOHN GRANT, 013

LOS ANGELES, CALIFORNIA CASING SPIDER AND THE LIKE App1ication filedMarch 23, 1928.

The present invention relates to casing spiders and analogous devicessuch as are employed for holding oil well casing drill pipe, tubing andthe like in vertically sus pended position.

Devices of the class mentioned usually comprise a ring or annular bodyproviding a central cavity of decreasing diameter downwardly, in whichcavity suitable wedges or slips are arranged so that the weight of theslips and the weight of pipe held thereby, causes the slips to descendin the cavity until they are securely wedged between the ring and pipe.In oil well practice the weight of the casing may be as much as tons,which,

acting on the ring thru the wedges imparts what would ordinarily be agreat bursting strain on the ring. Such strain however is largelyreduced or resolved into a vertical stress by reason of the fact thatthe angle of the wedging surfaces of the ring is within the angle offriction, or about 15 degrees included.

. Such angle gives rise to jamming on the part of the wedges to theextent that they do not release when the weight is relieved. Suchjamming is highly objectionable, not to mention the required operationof lifting the casing to release the slips, particularly when the casingis being lowered into the well.

The main object of this invention is to provide a device of the classdescribed in which the slips will release automatically when all-owed todo so and without necessity for lifting the casing. Actually, theinvention contemplates the employment of the weight of the casing forreleasing the slips, whereas in the usual device the weight is the causeof the major difiiculties.

Other objects and advantages of my invention will appear hereinafter.

In carrying out my invention I may employ the usual ring and slipsassembled within the ring. However, between the ring and the slips Iprovide means whereby downward motion or tendency on the part of theslips results in an upward movement or tendency on the part of the ring.I provide means for holding the ring down when desired and by Serial No.264,070.

releasing the last named means the weight of the pipe or casing is freeto act on the slips to move them down and to co-ordinately force thering upwardly. The means disposed between theslips and ring is radiallyexpansible on upward movement of the ring to release the slips. The ringmay be held in uppermost position while the slips are being removed orinstalled, and when allowed to gravitate back to normal position, thering acts to move all parts of the device into normal position.

I have illustrated one practical embodiment of my invention by theaccompanying drawings in which:

Figure 1 is a view in vertical mid section of such embodiment.

Figure 2 is a full plan view thereof.

Figure 3 is a view in side elevation thereof.

Figures 4 and 5 are similar to Fig. 1 and show the device in variouspositions as will be explained hereinafter.

' In the embodiment illustrated the slips 6 re of the usual form; beingprovided with external tapered surfaces 7 and equipt with cyebolts 8 orthe like for the receipt of the usual handles (not shown) whereby theslips are lifted into and out of place. The device provides the taperedbore 9 of decreasing diameter downwardly for receipt of the slips 6. Thebore 9, however is provided by an annular assembly of liner sections 10,10, 10, 10, which jointly provide that which may be termed a radiallyexpansible liner. The outer surfaces 11 of the liner are inclined toconverge upwardly and the liner as a unit may he said to possess aninternal bore of decreasing diameter downwardly, and an ex ternalcircumferential surface of decreasing diameter upwardly.

The liner is encompassed by the ring 12 adapted for vertical movementand coacting with the liner section so that downward movement of thering crowds the liner sections together in compact slip-holdingformation (see Fig. 1) while upward movement of the ring expands theliner to the slip releasing position in which the liner is shown inFigs. 4 and 5. Dovetail feather keys 14 hold the liner sections inconnection with the ring 12.

A base plate 15 is provided on which the liner sections rest at alltimes and upon which said sections are shiftable radially even undersuperimposed weight. Accordingly the under surfaces 16 of the linersections and the, upper surface 17 of the base plate are suitablymachined and lubricated if required. The base plate provides a largecentral aperture 18 around which the liner sections are disposed. Saidaperture is large enough to ass a pipe collar 19 or other annularenargement on pipe or casing 20.

The base plate is provided with circumferentially spaced horizontallydirected yokes 21 each opening horizontally as at 22 in the samedirection: considered circumferentially of the base plate. The plate isalso provided with underlying arms 21. The ring is provided withcorresponding radial pins 23 arranged to enter the open end of the corresponding yoke by reason of the ring being turned on the base plate inthe direction in dicated by the arrow in Fig. 2. The yokes are spaced soas to keep the ring concentric with the base plate and the aperture 18at all times. Each yoke is provided with an upper detent surface 24 sothat the pins may repose in the detents as shown in Fig. 5, to hold thering in lifted position and to hold the liner in fully expandedslip-releasing position.

The included angle of surfaces 7 and 9 may be within the angle offriction while the angle of surface 11 should be in excess of the angleof friction so that spreading action of the liner will impart an upwardtendency to the ring.

In considering the action of the device, reference is first had to Fig.1, which shows the device in normal pipe-holding position. In thisposition the slips are held against descent solely by reason of the factthat they cannot descend further without spreading the liner, and theliner cannot spread because the ring is held down by reason of the pinsbeing lodged each in under the corresponding yoke. To release the slipsthe procedure is as follows: The casin which is being lowered, issupposedly held y an elevator and lines (not shown) in such manner thatthe casing may descend an inch or two before taking up all slack in thelines. The ring, by means of bars 30, or by means of turning the casingdirectly, is turned until the radial pins are moved from under theyokes. The casing and the slips begin to descend toward the position inwhich they are shown in Fig. 4. This descent of the slips spreads theliner and lifts the ring. The casing has now been brought to rest by theelevator and lines. The slips may be lifted from the liner with theparts as shown in Fig. 4 but it is best to again turn the ring slightlyuntil the pins rest in the upper detent surfaces 24 of the yokes, asshown in Fig. 5. In the position shown in Fig. the weight of the ring isheld by the pins and yokes and the liner remains expanded fully asshown. Since the ring is not crowding the liner, the slips may bereadily removed leaving only the base plate, liner and ring respectivelyin assembly, as shown in Fig. 5. Now the device will pass anyenlargement such the pipe collar, either during raising or lowering ofthe casing.

When it is desired to again set the slips to hold the casing solely bythe device, the ring is turned slightly until the radial pins aredisposed in under the yokes as shown in Fig. 1. To do this the device,when in the position shown in Fig. 5 is manipulated so that the ringturns clock-wise a few degrees. This allows the ring to drop and crowdthe liners together. The ring is then turned anti-clockwise to move thepins under the yokes. The ring and liner sections are then ready toserve in the same capacity any casing spider or like device and allparts may then become disposed in the normal operative position in whichthey are shown in Fig. 1.

It will be apparent now that I have provided an annular slip receivingbody providing the requisite bore of acute angularity while capable ofeither automatic or manual operation to release the slips by changingthe elfective diameter of the said bore, all without subjecting thedevice to excessive bursting strains, and in which device all radialstresses may be wholly or partially resolved into vertical stresses sothat the weight of suspended pipe actually acts to release the slipsfrom the wedged position in which they are shown in Fig. 1, while theweight of the ring when in the position shown in Fig. 5 is depended uponto move the liner back to normal contracted position.

While I have shown and described a speciiic embodiment of my invention Ido not limit myself to any specific construction or arrangement of partsand may employ any construction or ar 'angement of parts withoutenlarging the scope of my invention, within the appended claims.

I claim:

1. In a device of the class described, a ring having vertical movement,slip wedges having vertical movement within said ring, and meanscoacting with said ring and wedges whereby downward movement of saidwedges imparts upward movement to said ring.

2. In a device of the class described, a ring having vertical movement,slip wedges having vertical movement within said ring, and meanscoacting with said ring and wedges whereby downward movement of saidwedges imparts upward movement to said ring, and releasable means forholding said ring down.

In a device of the class describes, an annular expa-nsible linerproviding a bore of decreasing diameter downwardly, slip .1 wedgesarranged in said bore to expand said liner by downward movement withregard thereto, and a ring encompassing said liner so as to be forcedupwardly by expansion of said liner.

4. In a device of the class described, an annular expansible linerproviding a bore of decreasing diameter downwardly, slip wedges arrangedin said bore to expand said liner by downward movement with regardthereto, and a ring encompassing said liner so as to be forced upwardlyby expansion of said liner, and releasable means for bolding said ringdown.

5. In a device of the class described, pipe engaging means movabledownwardly to engage and upwardly to release a pipe, holding meansassociated with said pipe engaging means so as to be urged upwardly bfdownwardmovement of said pipe engaging means, and other meansoperatively connecting said pipe engaging means and said holding meanswhereby movement is transferred from the first means to the secondmeans.

6. The device as in claim 5 and in which said holding means is mountedto gravitate from upper position to normal position.

7. In a device of the class described, an annular expansible liner, ahorizontal base plate supporting said liner, slip wedges within saidliner acting on downward movement to expand said liner, means urgedupwardly relative to said base plate by expansion of said liner; saidmeans being releasably locked to said base plate.

8. The device as in claim 7 and in which said last named means ismounted to gravitate from upper position to normal position to move saidliner from expanded position to normal position.

9. In a device of the class described, a base plate provided with anaperture, an expansible annular liner resting on said plate concentricto said aperture and providing an internal bore of decreasing diameterdownwardly and an external surface of decreasing diameter upwardly, slipwedges having vertical movement in said bore, and a floating ringembracing the said external surface of said liner.

10. The device as in claim 9 and further including releasable lockingmeans for looking said ring to said plate.

11. The device as in claim 9 and in which said ring is adapted for bothvertical and rotary motions; said device including releasable means forlocking said ring down to said plate operable by rotary motion of saidring.

12. In a device of the class described, a base plate provided with anaperture, an expansible annular liner resting on said plate concentricto said aperture and providing a bore of decreasing diameter downwardlyand an external circumferential surface of decreasing diameter upwardly,slip wedges having vertical movement in said bore, a floating ringembracing the external surface of said liner, and releasable means forlocking said ring to said plate against vertical movement; said meanscomprising radial pins projecting from said ring and horizontallydirected yokes to said base plate under which yokes said pins aremovable.

13. In a device of the class described, a base plate, a sectional linerhaving sections annularly arranged on said base plate for radialmovement, said liner providing a bore of decreasing diameter downwardlyand further providing an external surface of de creasing diameterupwardly, a ring fitted over said liner whereby radial expansion of saidliner Causes upward movement of said ring and whereby downward movementof said ring moves said liners from expanded position to normalposition, slip wedges in said bore and releasable means operable byrotary movement of said ring about the vertical axis of said liner.

ROBERT I-I. FOLSOM.

